template< class CharT, class Traits > bool operator==( const istreambuf_iterator<CharT,Traits>& lhs, const istreambuf_iterator<CharT,Traits>& rhs ); (1) template< class CharT, class Traits > bool operator!=( const istreambuf_iterator<CharT,Traits>& lhs, const istreambuf_iterator<CharT,Traits>& rhs ); (2) Checks whether both lhs and rhs are valid, or both are invalid, regardless of the stream buff

(1) explicit vector( const Allocator& alloc = Allocator() ); (until C++14) vector() : vector( Allocator() ) {} explicit vector( const Allocator& alloc ); (since C++14) (2) explicit vector( size_type count, const T& value = T(), const Allocator& alloc = Allocator()); (until C++11) vector( size_type count, const T& value, const Allocator& alloc = Allocator()); (since C++11

Appear in any type specifier, including decl-specifier-seq of declaration grammar, to specify constness or volatility of the object being declared or of the type being named. const - defines that the type is constant. volatile - defines that the type is volatile. mutable - applies to non-static class members of non-reference non-const type and specifies that the member does not affect the externally visible state of the class (as often used for mutexes, memo caches, lazy evaluation, and ac

size_type size() const; size_type length() const; Returns the number of CharT elements in the string, i.e. std::distance(begin(), end()). Parameters (none). Return value The number of CharT elements in the string. Exceptions (none) (until C++11) noexcept specification: noexcept (since C++11) Complexity Constant. Notes For std::string, the elements are bytes (objects of type char), which are not the same as characters if a multibyte encoding such as UTF-8 is

basic_string& insert( size_type index, size_type count, CharT ch ); (1) basic_string& insert( size_type index, const CharT* s ); (2) basic_string& insert( size_type index, const CharT* s, size_type count ); (3) basic_string& insert( size_type index, const basic_string& str ); (4) (5) basic_string& insert( size_type index, const basic_string& str, size_type index_str, size_type count ); (until C++14) basic_string&a

Usage protected access specifier

Objects, references, functions including function template specializations, and expressions have a property called type, which both restricts the operations that are permitted for those entities and provides semantic meaning to the otherwise generic sequences of bits. Type classification The C++ type system consists of the following types: fundamental types (see also std::is_fundamental): the type void (see also std::is_void); the type std::nullptr_t (see also std::is_null_pointer); a

Defined in header <locale> class locale; An object of class std::locale is an immutable indexed set of immutable facets. Each stream object of the C++ input/output library is associated with an std::locale object and uses its facets for parsing and formatting of all data. In addition, a locale object is associated with each std::basic_regex object. Locale objects can also be used as predicates that perform string collation with the standard containers and algorithms and can

Returns the result of specific arithmetic operation. Operator name Syntax Over​load​able Prototype examples (for class T) Inside class definition Outside class definition unary plus +a Yes T T::operator+() const; T operator+(const T &a); unary minus -a Yes T T::operator-() const; T operator-(const T &a); addition a + b Yes T T::operator+(const T2 &b) const; T operator+(const T &a, const T2 &b); subtraction a - b Yes T T::operator-

Defined in header <cwctype> int iswalpha( std::wint_t ch ); Checks if the given wide character is an alphabetic character, i.e. either an uppercase letter (ABCDEFGHIJKLMNOPQRSTUVWXYZ), a lowercase letter (abcdefghijklmnopqrstuvwxyz) or any alphabetic character specific to the current locale. Parameters ch - wide character Return value Non-zero value if the wide character is a alphabetic character, 0 otherwise. Example #include <iostream> #include &l